China’s Sinovac vaccine has been shown to be 78% effective against Covid-19 in Brazilian end-stage trials and offers total protection against serious cases of the disease, raising hopes that it can be used to immunize much of the world in development.
The Butantan Institute in Brazil, the São Paulo-based research center that tested CoronaVac in phase 3 trials, said Thursday that none of the volunteers who took the vaccine developed severe cases of Covid-19. More than 12,000 health workers participated in phase 3 trials in Brazil, the first country to complete Sinovac vaccine testing.
“It’s a great result,” said Luiz Carlos Dias, who is part of a Covid-19 working group of researchers at the University of Campinas in the state of São Paulo. “If it can prevent serious cases, hospitalizations, deaths, it will help us get out of this pandemic.”
The CoronaVac vaccine is less effective than those developed by Moderna Inc. and jointly by Pfizer Inc. and BioNTech SE which have been shown to have efficacy rates of 94.5% and 95% in the tests, respectively. But CoronaVac can be stored in a standard 36- to 46-degree Fahrenheit refrigerator, making it easier and cheaper to transport and store it in less developed countries, infectious disease specialists said.
Prashant Yadav, a global development center health specialist for the Washington Development Center, said 78% is a high enough rate for many developing countries to consider using the vaccine and that it may be good enough for the Organization to World Health is considering incorporating CoronaVac into its global distribution system.